decltype c++

#include <bits/stdc++.h>
using namespace std;

int main(int argc, char **argv)
{
    map<int, int> dict = {{1, 3}, {2, 4}};
    using dci = decltype(dict.cbegin());
    for (dci it = dict.begin(); it != dict.end(); ++it) {
        cout << it->first << ": " << it->second << endl;
    }
    return 0;
}